P0303 on GMC ACADIA — Cylinder 3 Misfire Detected

Q: "What does P0303 mean on a GMC ACADIA?"

"P0303 indicates: Cylinder 3 Misfire Detected. This is a ignition system code. 2 GMC ACADIA owners have reported this to NHTSA."

Q: "What are the most common causes of P0303 on GMC ACADIA?"

"Based on 2 NHTSA reports, the most commonly cited components are: Engine, Power Train,Engine. These percentages are based on the component field in owner complaints."

Q: "Is P0303 serious on my GMC ACADIA?"

"Of 2 NHTSA reports for this code on GMC ACADIA, none involved a crash or fire. However, any diagnostic code should be evaluated by a qualified mechanic."

Q: "What should I do if my GMC ACADIA shows P0303?"

"1) Check for recalls on your VIN at nhtsa.gov/recalls. 2) Get a professional diagnosis — a code alone doesn't identify the exact failed part. 3) Get 2-3 repair estimates to compare."

What P0303 Means on Your GMC ACADIA

P0303 is a diagnostic trouble code indicating: Cylinder 3 Misfire Detected. This code relates to the ignition system system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

2 GMC ACADIA owners have reported this issue to NHTSA across model years 2009-2010. Most reports come from the 2009, 2010 model years. The most commonly reported component is Engine (50.0% of reports).

Real GMC ACADIA Owner Reports

Source: NHTSA Complaints Database

"I was driving the vehicle on the highway with a steady acceleration. i noticed the car start to shake a little and the tachometer fluttering until it appeared the car down shifted. i took the vehicle to the dealer where they test drove the vehicle and found no problems."

— 2009 GMC ACADIA owner · ENGINE · Filed 03/10/2014

"At 80,000 miles, after pulling out of parking, when i applied brakes the car started making rumbling noise from the engine and lurched forward despite pressing on brakes to stop."

— 2010 GMC ACADIA owner · POWER TRAIN,ENGINE · Filed 07/22/2016

All reports filed by vehicle owners directly with the U.S. Department of Transportation.

📊 Complaint Trend by Model Year

1

'09

1

'10

Common Causes on GMC ACADIA

Based on NHTSA complaint component analysis for this vehicle.

ENGINE 50%

POWER TRAIN,ENGINE 50%

What To Do Next

1
Check for recalls on YOUR VIN
Go to nhtsa.gov/recalls and enter your VIN. If your vehicle is covered, repairs are free.
2
Get a proper diagnosis
A code alone doesn't tell you the exact failed part. A diagnostic at a shop ($50–$150) pinpoints the root cause before you spend money on parts.
3
Compare repair quotes
Get 2–3 quotes. Dealer vs. independent shop prices often differ 30–50% for the same repair.

Frequently Asked Questions

What does P0303 mean on a GMC ACADIA? ▾

P0303 indicates: Cylinder 3 Misfire Detected. This is a ignition system code. 2 GMC ACADIA owners have reported this to NHTSA.

What are the most common causes of P0303 on GMC ACADIA? ▾

Based on 2 NHTSA reports, the most commonly cited components are: Engine, Power Train,Engine. These percentages are based on the component field in owner complaints.

Is P0303 serious on my GMC ACADIA? ▾

Of 2 NHTSA reports for this code on GMC ACADIA, none involved a crash or fire. However, any diagnostic code should be evaluated by a qualified mechanic.

What should I do if my GMC ACADIA shows P0303? ▾

1) Check for recalls on your VIN at nhtsa.gov/recalls. 2) Get a professional diagnosis — a code alone doesn't identify the exact failed part. 3) Get 2-3 repair estimates to compare.